Related art may be viewed in light of the following structural formula (1): ##STR1## in which n is 4 to 5 and W and Y are different, one being CH and the other being N; R.sup.1 and R.sup.2 are independently selected from a group of substituents consisting of, among other moieties, hydrogen and halogen.
Wu, et al., discloses tranquilizing compounds of this structural type in J. Med. Chem., 15/5, 477-479 (1972) and in U.S. Pat. No. 3,717,634 patented Feb. 20, 1973. Additionally, three 5-substituted pyrimidinyl derivatives were disclosed. These correspond to the above structural formula wherein W is N and Y is C--NO.sub.2, C--NHSO.sub.2 C.sub.4 H.sub.9 and C--OH. No 5-halogenopyrimidines were specifically disclosed or claimed.
The following group of references represent related but less pertinent art.
Wu, et al., U.S. Pat. No. 3,907,801, issued Sept. 23, 1975, is a divisional of the above-cited '634 Wu patent. U.S. Pat. No. 3,907,801 claims the pyridinyl compound subject matter (e.g. W and Y are both CH).
Wu, et al., U.S. Pat. No. 3,976,776, issued Aug. 24, 1976, is also a divisional which claims the use of these compounds in a tranquilizing process.
Casten, et al., U.S. Pat. No. 4,182,763, issued Jan. 8, 1980, discloses and claims the use of buspirone (2), a specific compound of the above series, for treating anxiety. ##STR2## Wu, U.S. Pat. No. 3,398,151, issued Aug. 20, 1968, discloses and claims related compounds wherein the pyrimidine ring has been replaced by a phenyl moiety, unsubstituted or substituted (e.g., halogen).
Wu, et al., Journal Medicinal Chemistry, 12/4, 876-881 (1969) also reports work done with these phenyl analogs. No fluoro substituted phenyl derivatives are listed as examples or in any of the tables.
Finally, Temple, U.S. Pat. No. 4,423,049, issued Dec. 27, 1983, discloses and claims a series of 1-[4-(4,4-dialkyl-2,6-piperidinedion-1-yl)butyl]piperazines with 2-pyrimidinyl substituents in the 4-position which demonstrate useful anxiolytic properties. The pyrimidine ring in this series of compounds may either be unsubstituted or monosubstituted bearing a fluoro, chloro, hydroxyl, or trifluoromethyl substituent.
The present invention involves the discovery that the previously unsynthesized compound 8-[4-[4-(4-fluoro-pyrimidin-2-yl)-1-piperazinyl]butyl]-8-azaspiro[4.5]deca ne-7,9-dione possesses long acting antipsychotic activity. This pharmacological activity sets the instant invention apart from related pyrimidinyl compounds of the above references. These reference compounds mainly act as anxiolytics, with only minor antipsychotic action and that of short duration.